| In the South Hilly Area,the sowing quality is low due to the difficulty of adjusting the depth of the seed ditch and the low precision of the control,which affects the emergence of seedlings and crop yield.In this study,through the analysis and Research on the trenching device under the working state of rotary cultivator,in order to improve the consistency of sowing and ditching depth,the innovative design of the ditch depth adjusting device is carried out,and the automatic adjusting device of the ditch depth of rotary cultivator seed is developed.The device mainly includes ditch depth signal detection system and ditch depth control system.During operation,the ditch depth signal detection system collects information and then sends out ditch depth adjustment instructions.Through the height adjustment mechanism and horizontal adjustment mechanism of the ditch depth control system,the ditch depth is adjusted to achieve the purpose of stable and consistent ditch depth.The structure design,simulation and optimization of the regulating device are carried out by using Solid Works,Adams and other software,and the control system of the device is programmed by using keil programming platform to complete the prototype production,which is verified by indoor and field tests.The main results are as follows:(1)Through the dynamic simulation analysis of the dynamic movement track of the ground wheel mass in the profiling mechanism of the device by ADAMS software,it is determined that the groove depth adjusting device can better complete the profiling detection of the ground when the profiling ground wheel mass is 1.25 Kg and the forward speed of the machine is not more than 1.5m/s.(2)By using the static analysis function of the Simulation plug-in module in Solid Works software,the stress analysis and structure improvement of the adjusting four-bar linkage of the regulating device are carried out.The connecting rod is installed between the four-bar linkage,and the new linkage mechanism is 0.19 mm less than the existing linkage mechanism,and the structural stability is improved.(3)Carry out indoor soil trough simulation test to study and analyze the stability of the regulating device’s trenching depth.The trenching depth is 30 mm,50mm and 70 mm,and the stability coefficient of the trenching depth is 94.85%,94.31% and 95.40% respectively.The stability coefficient of the trench depth is positively correlated with the trench depth,and the overall stability is good,meeting the requirements of the standard stability coefficient(80%).(4)Further field experiments showed that the stability coefficients of trenching depth were 89.81%,91.88% and 91.40% respectively when the forward speed was 1 m / s and the trenching depth was 30 mm,50 mm and 70 mm.Under the same forward speed,the stability coefficient of trenching depth was positively correlated with the trenching depth.Under the same trenching depth,the stability coefficient of trenching depth was negatively correlated with the forward speed.(5)With the help of design expert software,combined with the quadratic regression equation and response surface,the significant relationship among the three factors is obtained.The most significant factors affecting the stability coefficient of the trenching depth are: the trenching depth h,followed by the forward speed V of the machine;the significant impact on the acceptance rate of trenching is: the trenching depth h = the forward speed V of the machine > the length L of the driving link.Finally,through the optimization analysis of the multi factor test,it is found that when the trenching depth h = 70 mm,the forward speed of the machine v = 0.5m/s,and the length of the driving link L = 40 mm,the trenching depth stability of the device is the best. |
PDF Full Text Request